Question

find the mean of the following frequency distribution x=4,6,9,10,15 f=5,10,10,7,8

Answer 1

sum of fi×xi=360
sum of fi= 40
mean = sum of fixi/sum of fi
=360/40
=9 thus mean of the data is 9

Answer 2

Freq = 4*5+6*10+9*10+10*7+15*8

==> 20+60+90+70+120

==> 170+190

==>FX= 360

for mean = fx/f

so 360/ 40 = 9 ( Answer )

hope it helps b